Writing a research paper (6) – presenting data with tables

Tables are often used in research papers to present data. In this blog post, I will explain when tables should be used, discuss common mistakes when using tables, and give a few tips to improve tables.

When tables should be used?

Tables are useful to display data. Tables should be used when there is enough data to display, and it is easy to read the table. Moreover, tables should be used when data is easily read in a tabular form.

Common problems with tables in research papers

Here are a few problems related to tables, often encountered in research papers:

1) The table does not have enough content. Generally, if a table is small or do not have enough content, then one should replace the table by text. For example, consider this table:

Algorithm

Runtime (s)

EFIM

10.0

FHM

11.5

EFIM-Closed

16.4

This table does not contain enough information since it can be replaced by a sentence “The EFIM, FHM and EFIM-Closed algorithms spent 10 s, 11.5 s and 16.4 s, respectively”. In this case, text should be used instead of a table.

2) The table is designed to be read horizontally. A table should never be designed to be read horizontally. For example, consider this table:

Algorithm

EFIM

FHM

UPTree

Runtime (s)

10.0

15

20

Memory (Mb)

45

60

70

It should be replaced by a table that can be read vertically:

Algorithm

Runtime (s)

Memory (Mb)

EFIM

10.0

45

FHM

15.0

60

UPTree

20.0

70

This table contains three columns, each representing an attribute. The first line shows the column titles. Then the following lines provide the data, described using these attributes.

3) Data that is also given in the text or in a figure. Normally, one should not present the same data using text, and also using a table or figure. If the data is given in the text. Then, there is no need to make also show a figure or table.

4) The data presented in the table is not meaningful. A table should be used to present data that is meaningful and relevant to the paper. If the content of a table is unimportant or irrelevant, it can be removed.

5) The text in the table is difficult to understand. Ideally, one should be able to understand a table without having to read the text. Thus, the table title and column titles should be chosen appropriately to facilitate understanding. In particular, if one uses abbreviations in a table, these abbreviations should be defined.

6) Numerical data that is not properly formatted or without units. A table should indicate the units used to represent numerical data such as seconds and megabytes. Moreover, numbers in a table should be properly formatted. In particular the number of digits after the decimal point should be appropriate for the data in terms of significant digits. Moreover, how numbers are formatted should remain consistent through the paper.

7) The table title is not meaningful or too long. Each table must have a title and the title must be meaningful, and not too long. For example, the following table has a short and meaningful title:

Table 1. Performance comparison of EFIM, FHM and UPTree

Algorithm

Runtime (s)

Memory (Mb)

EFIM

10.0

45

FHM

15.0

60

UPTree

20.0

70

A title is normally a short sentence or a part of a sentence.

8) The table is not formatted according to the requirements of the publisher. Before submitting a paper, one should also make sure that the paper meet the requirements of the publisher. Publishers often have a preferred table format.

A few more tips

To make a table more beautiful, one can align the table content. Typically, text is aligned to the left, while numbers may be centered or aligned to the right. For example:

Algorithm

Runtime (s)

Memory (Mb)

EFIM

10.0

45

FHM

15.0

60

UPTree

20.0

70

When a table is used to compare multiple objects, the best value(s) in each column may be highlighted in bold. For example, the following table compares three algorithms. The smallest value is considered to be the best one for each column, and thus it is formatted in bold. This allows to quickly see which algorithm has the best performance.

Algorithm

Runtime (s)

Memory (Mb)

EFIM

10.0

45

FHM

15.0

60

UPTree

20.0

70

Tables are great. But sometimes a chart is more appropriate than a table. It is thus important to consider other possibilities for presenting the data such as a chart or text.

Conclusion

This is all for today! Hope you have enjoyed this blog post about creating tables for research papers. If you have comments and other ideas or suggestions, please write a message in the comment section below.